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Imaging tool offers easy monitoring of redness in rosacea patients

Key clinical point: An image-based monitoring tool identified changes in redness in rosacea patients treated with topical ivermectin.

Major finding: Interobserver correlation was high (R2=0.82) for an imaging software tool and clinical scores in assessing redness in rosacea.

Study details: The data come from 21 adults with rosacea aged 24-81 years.

Disclosures: The study received no outside funding. The researchers had no financial conflicts to disclose.


"Accurate and consistent monitoring of facial erythema in rosacea patients is difficult to accomplish and has important clinical and therapeutic implications. An unmet need in both the office and clinical research trials is a method for overcoming the subjectivity in scoring erythema severity. For years, the clinician’s erythema assessment, a 4-grade system of none, mild, moderate, severe, has been utilized in clinical trials. However, it is prone to inter- and intra-observer variability. Visual examination is insufficient for subtle differences and the definition of severity is open for interpretation. For example if, after a therapeutic intervention, the patient has a larger area of less intense erythema, is this an improvement or worsening? Logger et al proposes a photographic process that they feel is superior to existing techniques that are expensive, time-consuming or limited in scope. Eichenfield, et al noted that comparison between baseline and postdose high-quality photographs improved investigator assessment in a clinical trial. As long as an investigator stays internally consistent, inter-observer variability becomes less important. Photographic demonstration of erythema improvement is generally satisfactory to the patient in the office setting and can become part of the permanent record. One question remains in my mind: why use ivermectin, which is not expected to improve the erythema of rosacea for a study evaluating severity of the erythema of rosacea?"

Hilary Baldwin, MD
Medical Director, Acne Treatment and Research Center
Brooklyn, New York
Clinical Associate Professor, Robert Wood Johnson Medical Center
Newark, New Jersey


Eichenfield L, Del Rosso JQ, Tan JKL, et al. Use of an alternative method to evaluate erythema severity in a clinical trial: difference in vehicle response with evaluation of baseline and postdose photographs for effectiveness of oxymetazoline cream 1.0% for persistent erythema of rosacea in a phase IV study. Br. J Derm 2019. 180(5):1050-1057.


Logger JGM. Skin Res Technol. 2020 June 14. doi: 10.1111/srt.12878.